I am trying to learn game development with the Unreal Development Kit and Unity, trying both out, and trying to get an idea how they work. For now, I'm mostly focusing on PC games.
How hard is the technical aspect of porting a PC game that I made in the Unreal Development Kit or Unity to another platform, such as Play Station 3, or Xbox 360? is there some kind of option where we can just select the target platform from a combo box and press deploy, or do we need to modify the game for each platform?